Add support for marking gen-class methods as native

Question

As far as I know, there is no support for creating a Java instance in Clojure with native methods. Everything else needed exists, but there is no way to get the right annotation on the method right now (similar to static).

Here's an example (http://benchmarksgame.alioth.debian.org/u64q/program.php?test=pidigits&lang=clojure&id=4) from Alioth perf tests where ASM is being used directly to generate a class with native methods where gen-class would have been perfectly adequate with this enhancement. (Equivalent Java: http://benchmarksgame.alioth.debian.org/u64q/program.php?test=pidigits&lang=java&id=2).

Suggested implementation is to mark ^{:native true} on a method and omit the body.

Answer 1

Reference: https://clojure.atlassian.net/browse/CLJ-1409 (reported by alexmiller)

Answer 2

Example implementation: https://github.com/clojure/clojure/compare/master...Saikyun:master